Resistance Inspection

HO2S Heater (Front and Rear) Resistance Inspection

1. Disconnect the H02S (Front or Rear) connector.




2. Measure the resistance between H02S terminals C and D using an ohmmeter.

Specification: Approx. 15.7 Ohms (Front, Rear)

- If not as specified, replace the H02S.
- If the H02S heater is okay, but PID value or PCM terminal 94 (Front), 93 (Rear) voltage are out of specification, carry out the "Circuit Open/Short Inspection".

Circuit Open/Short Inspection
1. Remove the PCM.




2. Connect the SST (104 Pin Breakout Box) to the PCM as shown.
3. Tighten the connector attaching screw.

Tightening torque
29 - 49 N.m {3.0 - 4.9 kgf.m, 22 - 36 ft.lbf}

4. Inspect for an open or short circuit in the following wiring harnesses by probing the applicable sensor and SST (104 Pin Breakout Box) terminals with ohmmeter leads.
- If there is an open or short circuit, repair or replace wiring harnesses.
- If there is no open or short circuit, replace the H02S.

Open circuit
- Power circuit (HO2S connector terminal C and ignition switch (IG1) circuit through common connector)
- GND circuit (HO2S connector terminal D and PCM connector terminal 94 (Front), 93 (Rear))

Short circuit
- Power circuit (HO2S connector terminal C and ignition switch (IG1) circuit through common connector to GND)
- GND circuit (HO2S connector terminal D and PCM connector terminal 94 (Front), 93 (Rear) to GND)

5. Reconnect the HO2S connector.